Noisy Outdoor AC Unit

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We have this Lennox outdoor AC unit 13ACX-042-230-16, where fan is loud and making noise while running.

Could it be a bearing lubrication or need to replace whole motor? So far, AC is running fine and no issues.

Appreciate all the help, thank you :)
 
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It’s probably the fan motor. Please take this with ever precaution….
Flip the breaker off at the unit (outdoors) and take a keen object and rotate the fan. It may reveal that the bearing in the motor is bad. I’ve had a unit with one fan blade that would rattle because of a loose brad. That caused a noise also.
 
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Make sure it's not the fan starting capacitor first (it's cheap and easy). I had that issue with a Lennox unit that was normally quiet.
 
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Yes, the motor bearings might benefit from lubrication. If lucky, the motor has oil ports. Otherwise it is a bit time consuming to remove the motor and disassemble it to lubricate the bearings. There's numerous links and Youtube videos. I maintain lots of greenhouse fan motors and I often get many more years service after lubing noisy bearings. I simply use 3-in-1 electric motor oil, but I am sure the experts all have their favorites.
 
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Did you clean the metal vents I have been taking the cover off the outside unit and I turn the breaker off. I use regular cold water out of the outside faucet to clean the vents. If the vents are too dirty and covered with mower grass and lint it can make the fan make more noise than usual. I didn't know I had to do this until last year ours was so bad the AC man took pictures of it. The system was only about 4 years old but I didn't know you had to clean them so I add this to my spring list of things to do.
 

maverickfhs

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Do you think removing the motor and then lubricating the shaft with 3 in one oil would help in terms of noise reduction and ensuring get a season out of this motor?

Or should I just go ahead and order the motor for replacement? Thank you :D
 

maverickfhs

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Make sure it's not the fan starting capacitor first (it's cheap and easy). I had that issue with a Lennox unit that was normally quiet.
Can you please elaborate? Like were there any other symptoms besides being super loud with capacitor being bad? Thanks
 
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Do you think removing the motor and then lubricating the shaft with 3 in one oil would help in terms of noise reduction and ensuring get a season out of this motor?

Or should I just go ahead and order the motor for replacement? Thank you :D
Best bet if it's the motor is to replace it. Once they start making noise, the bearings are already hurting and oilin may buy you some time. If you oil, don't use 3 in 1. A non detergent motor oil works good. An outgoing compressor can also make noise.
 

maverickfhs

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Best bet if it's the motor is to replace it. Once they start making noise, the bearings are already hurting and oilin may buy you some time. If you oil, don't use 3 in 1. A non detergent motor oil works good. An outgoing compressor can also make noise.
Would 2 stroke oil or gear oil or anything of that sort would work instead of 3 in one? Can compressor make super loud noise and would feel like coming from the fan area? Thank you.
 
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Would 2 stroke oil or gear oil or anything of that sort would work instead of 3 in one? Can compressor make super loud noise and would feel like coming from the fan area? Thank you.
Anything mechanical that moves or rotates can make noise, but only you can pin point which components is noisy. Several good suggestion were already made, now you need to physically examine the unit.
 
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Would 2 stroke oil or gear oil or anything of that sort would work instead of 3 in one? Can compressor make super loud noise and would feel like coming from the fan area? Thank you.
I like non detergent but any motor will work. Reason I do not like 3 in 1, when it was in a metal can years ago, the can always rusted badly. That itself told me something.

If there are no oil cups on your motor, your best choice is to replace the motor.
 
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My outdoor AC unit was noisy this season too. After a quick inspection I notice 3-4 exterior sheet metal screws were missing and causing excessive rattling. Trip to Home Depot for new ones and much better.
 
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